The conventional preparation of a patient's skin for surgery includes an extended period of cleaning using soap or the like, followed by the application of an antiseptic or disinfectant. The nature, duration and difficulty of this task depend heavily on the kind of surgical procedure to be followed, and on the size, shape and orientation of the body parts involved.
The oldest—and still widespread—method of applying the disinfectant is by dipping a swab, sponge or pad, held in forceps, into a dish of liquid and wiping it over the skin. Spent swabs/pads are continually discarded and fresh ones taken. The disinfectant is usually alcohol-based and may contain ingredients (such as iodine) that can irritate or burn the skin. It is important that the rate of application of solution be controlled, so that excess does not flow away to unintended areas, or form pools underneath the body or in hollows of the body where it may burn or irritate the patient, or indeed be a fire hazard if a cauterisation procedure is used. It is generally desirable to avoid mess or spillage whether on the patient's body or elsewhere. Another reason for keeping the applied liquid under control is to avoid liquid which has contacted one region of the patient's skin flowing away (or being carried on the applicator) so that it then contacts another region.
Conversely, and despite all the above factors indicating careful application, surgical prep is often done under severe time pressure and subject to safety and effectiveness there is every interest in doing it as quickly as possible.
Over the years many proposals have been made for hand-held applicator devices for applying surgical prep solution, incorporating an applicator head with a pad, sponge or other soft or deformable permeable element to be wiped across the skin, and a reservoir of the surgical prep solution—often contained in a handle of the device—communicating with the applicator pad to feed solution. This can make the application more efficient by obviating the repeated dipping of swabs and the discarding and replacement of spent swabs. The solution can be provided in a sealed sterile reservoir or cartridge, which can be opened by engaging it appropriately with an applicator head (e.g. by a spike built into the applicator head rupturing a membrane or film closure on the front of the cartridge). Operation of these devices can be easier and neater compared with the use of swabs.
Surgical preparation solutions can desirably be a mixture of two or more components. Commonly, these components cannot be pre-mixed in the container liquid, as they may interact and degrade.
WO2011/018621 discloses a twin chamber system. The first chamber is provided in front of the second, and the chambers are opened successively. Such devices can be difficult to assemble and/or fill, and care must be taken to ensure that in use, the two components are well mixed, and that the solution is uniform over the dispensing lifetime of the applicator.
Many applicators previously used have liquid containers which must be broken or pierced to release the liquid. U.S. Pat. No. 4,415,288, U.S. Pat. No. 4,498,796 and U.S. Pat. No. 6,488,665 disclose applicators which use internal piercers to open the liquid container.
The openers of the applicators described above result in a portion of the container being broken off or a flap being cut loose. This broken portion or flap may cause a reduction or variation in the flow rate over the dispensing lifetime of the applicator. It is particularly important to have a consistent and known flow rate in a device in which component liquids are mixed after the container is opened. Otherwise, mixing of the multiple components may be non-uniform over the dispensing lifetime of the applicator.
The present application presents proposals for applicators using pre-loaded liquid containers, and for new kinds of pre-loaded container for use with such applicators, addressing the above issues.